1. Field of Invention
The present invention relates to a short-circuit detection circuit and a short-circuit detection method; particularly, it relates to such short-circuit detection circuit and short-circuit detection method for use in a circuitry with a capacitive load circuit.
2. Description of Related Art
A power supply circuit usually provides over temperature protection (OTP) and output current limit (OCL) as short-circuit protection mechanisms for an output node.
However, with respect to the OTP mechanism, it takes tens of microseconds to generate a protection signal to trigger a protection action, because heat has a low conduction speed via a silicon substrate. When the output node is short-circuited, the circuitry may have already been damaged before the OTP mechanism triggers the short-circuit protection action.
The OCL mechanism is faster and therefore is better for use as the output node short-circuit protection mechanism; however, it immediately limits the driving capability of the circuitry when OCL occurs. Therefore, undesirable side effects may occur when the OCL mechanism is used as the output node short-circuit protection mechanism, especially when the circuitry is a power supply circuit which requires a higher driving capability to drive a capacitive load circuit.
In view of above, to overcome the drawbacks in the prior art, the present invention proposes a short-circuit detection circuit and a short-circuit detection method, which can be used in the power supply circuit that requires a higher driving capability to drive a capacitive load circuit.